1. Field of the Invention
The invention relates to a circuit layout for continuously displaying current and/or power consumption by an electrical load.
2. Description of the Related Technology
Measuring Instruments for measuring current intensity in amperes or power in Watts whereby the current or power intake of electrical devices are displayed, even continuously, are known in numerous embodiments. Such instruments are rather expensive, particularly for applications where a simple device indicating a low or high current is required.
Moving-iron instruments, used in the field of motor vehicle accessories capable of displaying the current or power intake of such instruments, are more cost-effective. However, since moving-iron instruments comprise mechanical parts, they are not inexpensive and long lived enough to be suitable for many applications. Furthermore, such instruments have small angular needle deflections of 90.degree. to 100.degree. , which is not linear relative to the power or current to be measured. Consequently, certain display or measuring ranges are highly compressed, which detrimentally affects the accuracy of the display.
In connection with electric household devices, such as for example washing machines, refrigerators, air conditioners, automatic hot plates, heating pads, etc., it is frequently necessary to ascertain the instantaneous current intake or power consumption, where the emphasis is on simple indications of a high or a lesser current flow rather than absolute values. Current or power measuring devices, even inexpensive moving-iron instruments, are too costly for such applications and cannot be made compact enough to be placed into a plug housing.